Abstract 145: Comparison of Outcome After Cardiac Arrest and Cardiopulmonary Resuscitation in Obese and Lean Rats
Background. Obesity and metabolic syndromes are associated with increased risk for coronary artery diseases and ultimately cardiovascular fatal events, including cardiac arrest. Indeed, obesity itself may contribute to a worse outcome following return of spontaneous circulation (ROSC) after cardiac arrest. We compared outcome of cardiac arrest and CPR in genetically modified rats (zucker) with obesity, hyperlipidemia, hypercholesterolemia and insulin resistance, and lean healthy rats. We hypothesized a worse outcome in obese rats compared to lean ones.
Methods. Thirty-five 20 wk old SD rats (470 g) and twenty-seven 20 wk old zucker rats (577 g) were used. Ventricular fibrillation was induced and untreated for 6 mins. CPR, including mechanical chest compression and ventilation with oxygen, was then initiated and continued for additional 6 mins prior to defibrillation. Animals were sacrified at baseline and at 2, 4 and 72 hrs after ROSC and heart, brain and blood collected for further biochemical and histological evaluations. Arterial and right atrial pressures were invasively monitored and coronary perfusion pressure (CPP) calculated. Myocardial function was echocardiographically assessed.
Results. 68% of obese animals were resuscitated compared to 87% of obese ones. Obese rats required a significantly greater defibrillation energy prior to ROSC (p<0.05). After ROSC, obese rats presented significantly lower heart rate, mean arterial pressure, CPP, ejection fraction and cardiac output compared to the lean ones (p<0.01, Table). Obese rats presented a 3-fold greater increase in post ROSC plasmatic troponin T compared to the lean ones (p<0.01, Table). None of the resuscitated obese rats achieved 72 hr survival in contrast to 62.5% of the resuscitated lean ones (p<0.01, Table).
Conclusions. In this model, obesity was a determinant for outcome of cardiac arrest. Obese rats showed worse post resuscitation cardiac function and survival compared to lean animals.
- © 2012 by American Heart Association, Inc.